Microbiological evidences for gastric cardiac microflora dysbiosis inducing the progression of inflammation

BACKGROUND AND AIM: Nowadays, anti-inflammation treatment is a promising approach for preventing tumorigenesis, and human microflora is closely related to inflammation. This study aimed to investigate the gastric cardiac microbiome and identify inflammation-related microorganisms for gastric cardiac inflammation. METHODS: We performed 16S rRNA sequencing on a total of 11 healthy and 89 individuals with different degree of gastric cardiac inflammation. Immunohistochemistry was used for verifying candidate bacteria. Phylogenetic reconstruction of unobserved states (PICRUSTs) was used for predicting the pathways involved by cardiac microflora. RESULTS: The resident phyla in normal were Proteobacteria, Firmicutes, Bacteroides and Actinobacteria and the dominant genus in normal were Halomonas, shewanella and Comamonas. In the progression of gastric cardiac inflammation, the diversity of cardiac microflora did not change(P > 0.05). However, the composition structure of cardiac microflora varied between healthy and inflamed tissues (P < 0.05). Meanwhile, there were 64 species parallel increased with inflammation degree, especially H. pylori, Lactobacillus Spp.. Additionally, inflammation-related species were detected (P < 0.05), including H. pylori, Acinetobacter ursingii, Streptococcus agalactiae. Higher H. pylori colonization was positively related to the progression of cardiac inflammation (gamma coefficient = 0.678, P< 0.001), and it also influenced the cardiac microbial community structure. Cardiac microflora also participated in DNA repair pathways, and affected by the relative abundance of H. pylori(P < 0.0001). CONCLUSIONS: Cardiac microflora dysbiosis promoted the progression of cardiac inflammation, especially H. pylori, providing.